tinoknell



4 Sheets-Sheet 1 (No Model.)

B. TINGKNEQLL.

. VALVE GEAR.

Patented Mar. 8 1887 N. PETERS. Fl-olomhn m hon Washington. D. c.

(NQ Model.)

' 4 Sheets- Sheef 2. E. TINOKNELL.

. VALVE GEAR.

Patented ar. 8, 1887.

I Ira/071121.

n. PETERS. Phnlo-Lflhographer. Wnsmrvginn. n c.

(No Model.) 4 SheetsS11eet 3. E. TINGKNELL.

VALVE GEAR.

No. 358,996. Patented Mar. 8, l

lffrlrllz/ (No Model.) 4 Sheets--Sheet 4. E. TINOKNELL.

VALVE GEAR. No. 358,996. Patented Mar, 8, 1887.

I l A N ETERS. Pmlo-Enho whun Waxhingkm. D. c

UNITED STATES PATENT OFFICE.

EDWARD TINCKNELL, OF NElV SVVINDON, COUNTY OF VILTS, ENGLAND.

VALVE-GEAR.

SPECIFICATION forming part of Letters Patent No. 358,996, dated March 8, 1887.

Application filed October 19,1886. Serial No. 216,656. (No model.) Patented in England January 7, 1886, No. .293.

To aZZ whom it may concern.-

Be it known that I, EDWARD TINOKNELL, a subject of the Queen of Great Britain, residing at New Swindon, in the county of WVilts, England, have invented new and useful Improvements in or applicable to Steam-Engine Valve- Gears, (for which I have obtained a patent in the following country, Viz: Great Britain, by Letters Patent No. 293, dated January 7, 1886,) of which the following is a specification.

My invention relates to the construction of whatI term a valve-gear corrector, consisting of an oscillating link and sliding block worked from a fixed point, and is applicable, where one eccentric is used, for one-way-working engines, and also to stationary, marine, and locomotive engines fitted with any kind of valve-gear.

In order to enable my invention to'be fully understood, I will describe the same by reference to the accompanying drawings,in which- Figures 1 to 7 are sectional elevations showing myimprovements applied to the link-motion of the valve or valves of steanrengines having a reversing motion. Fig. 8 is an elevation of the corrector, and Fig. 9 is a diagram illustrating the results of the use of my valve-gear corrector. Figs. 1 to 7 are drawn to a scale of about one-sixteenth full size, and Figs. 8 and 9 about one-quarter full size.

Similar letters in Figs. 1 to 8 represent similar parts.

In Fig. 1 my corrector takes the place of andserves thepurposeofa valvespindleguide, and the said figure represents the most advantageous mode of its application, as, the link being suspended, the motion will work to the best advantage.

Referring to the said Fig. 1 and to Fig. 8, a is the corrector or oscillating link, having a slot, at, the said link being attached at a to the motion-plate, framing, guide-bar, cylinder, or bed-plate of the locomotive or other engine to which it is desired to apply my invent-ion, the corrector being applicable to all kinds of valvegear motion. forking within the slot at is a block, a loosely attached to the valve-spindle c of the slide-valve c". h h are the usual eeeentrics, attached to the usual reversing-link, h, by the eccentric-rods 7r 7f, the slide-block working in the said link being connected to the corrector a by means of the slide-rod b and link I). The link I) is attached to the oscillating link a at a shorter distance from its pivot a than the valve-spindle 0, thereby giving the slide-valve a longer travel than if the link I) were connected directly to the valve-spindle c, in the usual manner, or to the eccentric only, as in a non-reversing engine.

The dotted lines shown in Fig. 8 at (Z and 6 indicate the extreme extent of travel of the valve-spindle 0' when working with the re versing-link h in full gear, and the radius at f to the center line, 0, of the valve-spindle c at 9 shows the extent to which the corrector a moves over the block during its forward and backward motion, consequently lengthening or shortening (as the case may be) the distance from a to 0, thereby giving a motion to the valve which varies in speed. As will be seen by reference to the diagrams shown in Fig. 9, in which the full lines indicate the gear corrected and the dotted lines the gear uncorrected, and to the explanation hereinafter given, I obtain a quick opening and retain the maximum port opening during a great portion of the stroke of the pistonthat is to say, the valve arrives at a point of rest which equals the length of the straight portion of the slide-valve diagranrlines, resulting in a very quick cutoff. At the same time I obtain eighty per cent. additional expansion-space.

The diagrams illustrated in Fig. 9 were taken from a full-sized model in the first,third, fifth, and eighth notches. The said figure shows the cylinder-face upon which the slide-valve works in section, and the measurements. of which-videlicet, the width of exhaust-port, width of bar,width of steam-ports, and width of metal outside the steam-ports-are drawn extended,so as to represent the length of stroke. The said extended part is divided into the number of inches equaling the piston travel viz., twenty-four inches-and the spaces on which the full and dotted diagramdines are drawn are intended to illustrate the steanr ports on both sides of the exhaust-port. From these lines or slidevalve diagrams the conditions of the valve movement can be seen, or the true position of the valve in relation to all points of thepiston travelvidelicet,the point of lead, port-opening, duration of full portto the point of cut-off.

The proportion of measurements shown in Fig. 8 will be found suitable for one inch and seven-eighths outside lap, giving one inch and one-eighth port-opening and three-sixteenths of an inch lead. In this case the eccentric sheaves would be moved forward, increasing the angular advance in order to overcome the additional lap and equal the desired lead.

It will be seen from the valve diagram, Fig. 9, that the cut-off is later at the forward stroke than at the back stroke, the corrector being adjusted for this purpose, so as to render the beat of the engine more uniform.

In Fig. 2 the same results are obtained by means of the correotor as by the arrangement shown in Fig. l; but the link is not shown suspended, as in Fig. 1.

rector is equally applicable to any kind of valve'gear motion.

Forward gear.

g? g l Lead of valve. Slide opens. Steam cut off. Exhaust opens. 7 Exhaust closes.

notch. valve.

5 Front Back Front Back Front Back Front Back Front Back stroke. stroke. stroke. stroke. stroke. stroke. stroke. stroke. stroke. stroke.

Inches. n 1 4196 1 t 1 11 1 11 H: 2 1 a: 1% 1k 1 F F -B 1 6g 1;; 1% 135 125 20% 20, 20;}, 20,9

F B B 3 a a a s 18 .1. a a a F n F F F B 3 e a i 19 1 a 19 a B F A 5 it i i 1% b x;

1; F B 5 513G 23 1 a 1 B 1 1: G1 a s 1G1: 1G5

11 n n A.. a 3 g g a g at 2;, 11;; mg 11g- 11};

n F 15 F 1; n n B 3 45 g s t g e 21;; 2, 12 12 12 12 Backward gear.

Number Travel of of Lead ot valve. Slide op ens. Steam cut ofi". Exhaust opens. Exhaust closes. notch. valve. 1

Front Back Front L Back Front Back Front Back Front Back stroke. stroke. stroke. 1 stroke. stroke. stroke. stroke. stroke. stroke. stroke.

Inches. 1 1 B A 1 1i a z 1 .5 2 1 n 2 1.

B 1 6,; i 1 5 1, 12; 13 20; 19g 20g. 19;

F F I n 5 A 3 353 a i g- 2 53 in 14s 20g- 20, 203 20 F n F l i B B J 11 1E 1- li 9} 3 13 a Q P A 5 i a l a l i i .1 18 a 18 1? 1 i F r B 5 1 1 c 1 c 5 i 1 5 6 B I3 B 8 3 1 .1 s a 4 a 12 a F F E l 1 F F B 3 it it a: I t I t x"; 2 i 2- 2- ft The above table, showing the working of the slide-valve, was taken from the link-motion illustrated in Fig. 1, equaling twenty-four inches stroke or piston travel. on the lines marked A indicate the gear workapplied, while those 011 the lines marked B indicate the gear as shown on the drawings with the corrector applied. The letter B The figures I against the figures denotes the bare meas urement, while the letter F denotes the full ing in the usual manner without the corrector measurement. It will be seen from the table that the same was taken with the reversinghandle in four different positions-videlicet, in the first, third, fifth, and eighth notches, the first notch being full-gear and the eighth midgear, or, in other words, out of gear, so that the difference between the two conditions of working shown by the figures on lines A and B can be clearly seen. A supplies steam for nearly seventy-five per cent. and B for fiftyfive per cent. of piston travel. Both A and B give the same amount of port-opening; but B cuts off the supply more quickly than A, owing to the valve or valves opening and closing the cylinder-ports more quickly with 13 than with A. Bs action upon the valve or valves is almost equivalent to the Corliss gear, and the table shows that in the first. notch, or at full-gear working, the space for eX pansion is increased eighty per cent.,whereby the steam is utilized to a much greater advantage, and in the eighth notch, or at midgear working, it will be seen that B is working more expansively than A. Consequently the cut-off is rendered quicker or shorter, retaining approximately the same points of exhaust as at present The valve which gave the figures on lines A had one and one-eighth inch outside lap. That which gax e those on lines B had two and onesixteenth inches outside lap. The valves for both A and I3 had no inside lap. It must be understood that any extent of outside lap may be adopted, the valve-gear corrector being adjusted accordingly, allowing the eccentric sheaves to retain their original amount of throw.

The advantages to be derived from the employment of my invention over the present system of working are numerous, as will be seen from the following results: It gives equal port-openings in backward and forward gear, as well as back and front stroke 011 each gear, and also retains equal leads. It can be adjusted to give equal cutoff at any desired point of the piston travel, giving at the same time the required amount of port-opening. Eighty per cent. more space for expansion is obtained than can now be procured by any valve-gear, excluding the Corliss gear. I am enabled to open the exhaust at an earlier part of the stroke than hitherto, thereby insuring a much more perfect exhaust before the return-stroke of the piston, consequently dispensing with a large amount of back-pressure. The steam is regulated so as to utilize the same to the best advantage in the one cylinder. A saving of over twenty-five per cent. in fuel and water will be effected.

The application of the corrector does not necessitate any alteration to whatever valvegear it may be attached, as the same throw and position of eccentric sheave or sheaves, length of eccentric-rods, and position of weighshaft can be employed as at present, in addition to which the corrector will allow of any desired alteration in lead, port-opening, or cutoff being made without interfering with I ing.

any conditions that may be required to remain. Being able to obtain the maximum port-opening at an earlier part of the stroke and to retain the same for a large portion of the travel of the piston, in addition to obtaining a quick cut-off, which prevents wire-drawing thesteam,

the expansion commencing at, say, half-stroke seventy-five per cent. of stroke where the cut 7 off now takes place-is converted into friction on the axle bearings, boxes, &e., whereby much power or turning force is lost. This loss would be prevented by adopting the early and quick cut-off, and the engine would be at liberty to work more freely, and consequently get up speed more easily.

By the use of my invention the travel of the valve will equal approximately six inches, whereas under the present system it only equals four and a half inches at full-gear work- Consequently the six inches travel effects a more perfect lubrication on the faces.

My corrector, when applied to Hackworths gear, Fig. 7, will correct the defects of that gear, rendering it adjustable for any desired range of cut-off, whereas the required portopening can only be obtained now by adopting a very late cut-off, which necessitates the notching of the link to a point of very acute angle, whereby the gear is rendered almost impracticable.

The arrangement of the corrector is so simple and effective that very little additional eX- pense is incurred in applying it to any existing valve-gear.

Having now particularly described and as certained the nature of my said invention'and in what manner the same is to be performed, I declare that I do not claim the oscillating link worked or actuated by the guide-bar or eccentric rod or rods; but

What I claim is- 1. In a valve-gear, the combination of the valve-spindle with aguide-bar, the connectinglink, the oscillating link, and the sliding linkblock, and means for operating the guide-bar, substantially as shown and described.

2. The valve-gear corrector described, consisting of the combination, with the valvespindle, of the slotted oscillating link a a, block a eccentrics h h, eccentric-rods h h, reversing-link h, and slide-rod b, all substantially as and for the purposes set forth.

\Vitnesses: E. TINCKNELL.

F. SAUNDERS, WM. TURNER. 

